Category Archives: galaxies

Dear colleagues far and wide. I’m delighted to share the news that we are having a job search in Astrophysics! Please note the link’s contents, and share it to those who might be interested. Thanks! https://usccareers.usc.edu/job/los-angeles/assistant-professor-of-physics-and-astronomy/1209/5668638 -cvj

Recall that some years ago the Hubble telescope found a rude message in the sky:

It is said that many were offended by this sign. Some even thought it may have been left by their God as a sort of crude final message for those seeking meaning in the skies. Other, perhaps less imaginative people just figured it’s a random combination of shapes people are projecting onto.

Well, after much more searching through the sky for the perpetrator of the crime, it seems that the Hubble instrument may have caught a suspect on camera:

Of course, until the entity is brought in for questioning, it should be granted the presumption of innocence. (And even if it was its hand, it may have all been a big celestial misunderstanding…)

-cvj

P.S. The first NASA/ESA Hubble image is from a detail of gas clouds in the Carina nebula, and more can be found out about it here.

In the second NASA/ESA Hubble image the arcs of a circle that form the “head” shape are actually a gravitational lensing effect. 100 years ago this year Einstein published his General Relativity which shows, among other things, […] Click to continue reading this post →

…Or at least, not always the fire you’re looking for. So, as suspected for several months now, the signal seen by BICEP2 experiment and dubbed “a smoking gun” type of direct evidence for cosmic inflation (for which we have lots of strongly suggestive indirect evidence, by the way) is likely an artefact of the effects of galactic dust. I spoke about this in a post a while back, so I won’t repeat myself here. What everyone has been waiting for has been the results of a joint analysis between the BICEP2 people and the ESA’s Planck mission. The Planck satellite, you may recall from reading here or elsewhere, is also designed to carefully study the polarisation of the cosmic microwave background (the earliest light to shine in the universe), and so can (through thorough analysis of the effects of dust that it has measured independently) help rule in or out whether there is a signal. Planck studies essentially the whole sky, not just the patch that BICEP2 was carefully looking at, and one of […] Click to continue reading this post →

As promised on Tuesday, below you will find my Screen Junkies interview where I chat with Hal Rudnick about some of the science in Interstellar. We covered a lot of topics and went into a lot of detail, but a lot of that is on the cutting room floor in order to make a svelte (but relatively generous) ten minute cut. I hope you enjoy it. (See my earlier thoughts on why I think scientists need […] Click to continue reading this post →

After emerging from a spectacular 70mm viewing of Interstellar at the Arclight Dome last night, I was grinning from ear to ear, which is unusual these days after seeing a film in this subject area (science fiction, space travel, the future of humanity, etc). (And by science fiction here I mean proper science fiction, not space opera or space adventure. There’s a lot of that and some of it is fun and makes me grin too, like this Summer’s Guardians of the Galaxy. But that’s not at all the same sort of thing.)

I’m not going to go into any details, since I am very tired of the practice of talking about films to the extent that you say so much of what happens that it is impossible for someone to enjoy watching the film unfold in front of them without knowing what comes next, the way I like my films best. So I’m not going to ruin things for you.

Everybody keeps asking me “what did you think of the science?” since they know that there’s a lot of stuff in there that relates to my subject area and interests. Many seem to want me to pronounce on what’s “good” and whats “bad” about the science, as though I’ve (like many scientists in the public sphere seem to have done) elected myself some sort of guardian of scientific ideas. Let me say two things. The first is that this is a science fiction film, not a science documentary. I’m already hearing all sort of humourless declarations about this and that and the other being wrong and how shameful it is, as happened with Gravity last year. Done right, such discussions can be an opportunity to teach a bit about science ideas, but most often it just comes across as being a smartass, which is a bit tedious, and leads me to my second point.

You may recall that back in June I had a chat with Hal Rudnick over at Screen Junkies about science and time travel in various movies (including the recent “X-Men: Days of Future Past”). It was a lot of fun, and people seemed to like it a lot. Well, some good news: On Tuesday we recorded (along with my Biophysicist colleague Moh El-Naggar) another chat for Screen Junkies, this time talking a bit about the fun movie “Guardians of the Galaxy”! Again, a lot of fun was had… I wish you could hear all of the science (and more) that we went into, but rest assured that they* did a great job of capturing some of it in this eight-minute episode. Have a look. (Embed below the more-click):
[…] Click to continue reading this post →

I was sent an interesting link a while ago* that I thought I would share with you. It is a really good discussion about Dark Energy – what do we think it is, why we think it exists, why some think it does not, and how to move forward with the discussion of what is, after all apparently *most* of our universe. It is a panel discussion that was hosted by the Institute for Arts and Ideas (which I *love* the idea of!). The discussion is described on the site as follows:

Dark energy is supposed to make up two-thirds of the universe. But troublingly CERN has yet to find any evidence. Have we got our story of the universe wrong – might dark energy be the aether of our time? Do we need a new account of the universe, or is it too soon for such radical solutions?

Ok, the “troublingly CERN has yet to find any evidence” part puzzles me a bit, since nobody’s really expecting CERN to find any evidence of it, in any large scale experiments that I’m aware of (please correct me if I am wrong)… Is the writer of the abstract confusing Dark Energy and Dark Matter? Even then I think it is an odd phrase to lead with, especially if you don’t mention the huge amount of evidence from astronomy in the same footing… but I imagine the abstract was maybe not written by a physicist?

Nevertheless, I strongly recommend it as a thought-provoking discussion, and you can find it embedded below. Do also check out their many other interesting […] Click to continue reading this post →

Don’t forget that on the USC campus on Friday at 4:00pm, we’ll be kicking off the Collecting the Cosmos event! It will be in the Doheny library, and there’ll be a presentation and discussion first, and then a special opening reception for the exhibition. Be sure to get yourself on the waiting list since there’s some chance that you’ll get in even if you have not RSVPed yet. (The image is from the Visions and Voices event site, and includes parts of the artworks – by artists Victor Raphael and Clayton Spada – to be included in the exhibition, so come along and see.) The event description says, in part: […] Click to continue reading this post →

I just spotted (a bit late) that Steven Weinberg (one of the giants of my field) has written a piece in the New York Review ofBooks entitled “Physics: What We Do and Don’t Know”. I recommend it. He talks about astronomy, cosmology, particle physics, and by casting his eye over the arc of their recent (intertwined) histories of ideas, experiments and discoveries, tries to put the Standard Models of particle physics and of cosmology into perspective.

Well, the day is here. The Planck collaboration has announced a huge amount of results for the consumption of the scientific community and the media today. The Planck satellite looks with unprecedented precision at the very earliest radiation (“cosmic microwave background radiation”, CMB) from the universe when it was very young (a wee, cute 380,000 years old) and helps us deduce many things about what the universe was like then, and what it is like now. Here’s one of the representations of the universe using the new sky mapping Planck did (image courtesy ESA/Planck):

There’s a ton of data, and a raft of papers with analysis and conclusions. And there’s a very nice press release. I recommend looking at it. It is here, and the papers are here. The title of the press release is “Planck reveals an almost perfect Universe”, and some of the excitement is in the “almost” part. A number of anomalies that were hinted at by the previous explorer of the CMB, WMAP, seem to have been confirmed by Planck, and so there are some important things to be understood in order to figure out the origin of the anomalies (if they ultimately turn out to be real physics and not data artefacts). [Update: Andrew Jaffe has two nice posts I recommend. One on the science, and the other on the PR. Jester also has a nice post on the science from a particle physicist’s perspective.]

What is the title of my post referring to? Well, the refined measurements have allowed us to update some of the vital statistics of the universe. First, it is a bit older than previous measurements have indicated. The age is now measured as 13.82 billion years. (I’m already updating pages in the draft of my book…) Second, the proportion of ingredients […] Click to continue reading this post →

You might not know the name Maurice Murphy, but I am certain that you are likely to know – and maybe even be very familiar with – his work. His is the principal trumpet playing the lead themes in very many films with music by John Williams. I have for a long time been very impressed with how so many of those themes trip so easily off the tongue (physical or mental) and seem to fit together so well (just hum the Star Wars theme, and then follow it by the Superman theme, then the Indiana Jones theme, and so on). A lot of this is due to the fact that Williams (like most good composers) is a master at recycling and modifying, creating a cluster of much loved (deservedly) themes that accompany some of our favourite movie-going memories, but I now think that the other reason is that you’re hearing them all played by the same voice! That voice is the playing of Maurice Murphy, the truly wonderful trumpeter who Williams would specifically request to play the lead on recordings of his film music. Murphy died recently, and you can dig a bit more about him and explore what I’ve been telling you further by going to the London Symphony Orchestra’s site devoted to him […] Click to continue reading this post →

You can read a bit about the work of my colleague Elena Pierpaoli and her postdocs and students in this article in one of USC’s in-house publications. It focuses on the Planck observatory (image right from NASA/ESA), which we’ve discussed here before. (Recall the launch?) There’s a lot of exciting physics about the very young universe to be discovered as more data from the mission get gathered and analyzed.

My friend, The Universe co-contributor, and colleague Amy Mainzer (JPL) is rubbing gloved hands together in the chilly night air up at Vandenberg. Well, ok, if not this very moment, she probably will be at various points this evening and into the wee hours of the morning. The launch pad for WISE (the mission on which Amy is deputy project scientist) is set, and everything is ready to go! See my earlier post about what […] Click to continue reading this post →

Once again I’m excited about a new piece of machinery. This time it is a space mission again. There have been several remarkable missions launched (many in very recent years), doing all sorts of excellent science, helping us discover all sorts of things about our universe, near and far, young and old. I’ve spoken about (and sometimes followed live) the launches of some of them here on the blog, or spoken about the science results they’ve helped produce. See the graphic on the right for some of them.

Well, very soon (possibly as early as December 9th), there will be the launch of WISE, the Wide-field Infrared Survey Explorer! I learned from my friend, colleague and fellow presenter on History Channel’s The Universe, JPL’s Amy Mainzer, who is a senior scientist and the deputy project scientist on the WISE mission, that they made a series of exciting videos about WISE for you to learn about the science that WISE will do and how it will go about […] Click to continue reading this post →

Friday evening was very enjoyable indeed, with some arts and literature near the start, and live scientific research toward the end. It began with a nice trundle across town on the 920 bus, when it eventually arrived (why are there still so many long gaps in the 720 and 920 schedules at crucial times of the day?) heading over to Westwood to the UCLA campus. I listened to music, read Jonathan Gold’s column in the LA Weekly, and listened to conversations around me. I got to Westwood and Wilshire after half an hour or so and walked up to campus and to Royce Hall, getting coffee on the way and even stopping in to an AT&T store to check on something. The campus was surprisingly quiet at 7:30 or so and I made my way over to Royce Hall, sending a text to a friend about later.

Besides the environmental reason I like to try to take public transport, it is also nice to plan it out and then be 15 minutes early and nice and relaxed before an event, and not be arriving all stressed due to traffic and then worried about parking and so forth. The show started late (as everything does in LA because there is a tacit assumption that everyone will be late due to traffic and parking and so people mostly were late because, of course, they know this assumption is in place. (At the 8:00pm actual official start time only about 20% of the audience that would arrive in the next 15 minutes were actually seated.)

The event, you’ll recall, was all about Margaret Atwood’s new book Year of the Flood. The author and the actors and musicians came onto the nicely decorated set and started with one of the songs specially written for the event. There is a limited set of engagements in 16 or 20 (I’ve forgotten) cities performing this reading and this is one of them. Margaret Atwood was the narrator and there were three actors reading the parts of three characters from the book. A central cult/religion that appears in the book (and the previous book with […] Click to continue reading this post →